Radio Operation Switch Based on GPS Mobility Data

ABSTRACT

Systems and methods are disclosed for providing a radio operation switch based on mobility data. In one embodiment, a mobile base station is disclosed, comprising: a global positioning system (GPS) module for determining a current location of the mobile base station; a velocity module coupled to the output of the GPS module for determining a current velocity of the mobile base station; and a controller, the controller configured to perform steps comprising: determining the current velocity of the mobile base station using the velocity module; comparing the current velocity to a threshold; and switching, based on the comparison, from a first radio band to a second radio band.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation under 35 U.S.C. §120 of U.S. patentapplication Ser. No. 14/864,194, filed Sep. 24, 2015, entitled “RadioOperation Switch Based on GPS Mobility Data,” which itself is anon-provisional conversion of, and claims the benefit of priority toU.S. Provisional Patent Application No. 62/054,442, entitled “RadioOperation Switch Based on GPS Mobility Data,” filed on Sep. 24, 2014,the entire contents of which are hereby incorporated by reference forall purposes. In addition, this application incorporates the followingapplications by reference in their entirety: U.S. patent applicationSer. No. 13/889,631, entitled “Heterogeneous Mesh Network and aMulti-RAT Node Used Therein,” filed on May 8, 2013; U.S. patentapplication Ser. No. 14/034,915, entitled “Dynamic Multi-Access WirelessNetwork Virtualization,” filed on Sep. 23, 2013; U.S. patent applicationSer. No. 14/183,176, entitled “Methods of Incorporating an Ad HocCellular Network into a Fixed Cellular Network,” filed Feb. 18, 2014;U.S. patent application Ser. No. 14/024,717, entitled “HeterogeneousSelf-Organizing Network for Access and Backhaul,” and filed on Sep. 12,2013; U.S. patent application Ser. No. 14/146,857, entitled“Heterogeneous Self-Organizing Network for Access and Backhaul,” andfiled on Jan. 3, 2014; and U.S. patent Application Ser. No. 14/571,250,entitled “Virtualization of the Evolved Packet Core to Create a LocalEPC,” filed on Dec. 15, 2014.

BACKGROUND

A base station providing access service tries to provide coverage to awide area, the area typically being determined by user density. Theradio interference generated by the node in a fixed deployment is fairlyconstant and does not cause neighboring nodes to frequently switchoperations such as coverage, transmit power, or cell ID. A mobile node,on the other hand, provides coverage only to devices within the samemobile domain. One of the requirements for a mobile base station is tominimize disruption to the surrounding environment while travelling.This requirement is not met when a mobile base station in a movingvehicle causes mobile nodes to attach and then immediately detach as ittransits through an area.

SUMMARY

Systems and methods are disclosed for providing a radio operation switchbased on mobility data. In one embodiment, a mobile base station isdisclosed, comprising: a global positioning system (GPS) module fordetermining a current location of the mobile base station; a velocitymodule coupled to the output of the GPS module for determining a currentvelocity of the mobile base station; and a controller, the controllerconfigured to perform steps comprising: determining the current velocityof the mobile base station using the velocity module; comparing thecurrent velocity to a threshold; and switching, based on the comparison,from a first radio band to a second radio band.

In another embodiment, a method for providing access to mobile devicesat a base station is disclosed, comprising: determining a currentlocation of the base station; determining, based on the currentlocation, a current velocity of the base station; comparing the currentvelocity to a threshold; and switching, based on the comparison, from afirst radio band to a second radio band.

In another embodiment, a method for providing access to mobile devicesat a base station is disclosed, comprising: determining a currentlocation of the base station; determining, based on the currentlocation, a current velocity of the base station; comparing the currentvelocity to a threshold; and reducing transmit power at the base stationif the current velocity exceeds the threshold.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic drawing of a mobile base station deploymentscenario, in accordance with some embodiments.

FIG. 2 is a flowchart depicting a method for changing access networkpower, in accordance with some embodiments.

FIG. 3 is a schematic diagram of an enhanced base station, in accordancewith some embodiments.

DETAILED DESCRIPTION

A backhaul connection typically handles high speed handovers betweenfixed-location base stations while not losing the anchor. In802.11-based WLANs, the 802.11p amendment defines wireless access invehicular environments and speeds, at frequencies within the 5.9 GHzband, which is 75 MHz wide. This band is not wide enough to allowoptimal high throughput operation with channel bonding. In 802.11(Wi-Fi) channel bonding is used in Super G technology, referred as 108Mbit/s. It bonds two channels of standard 802.11g, which has a 54 Mbit/sdata signaling rate. In IEEE 802.11n, a mode with a channel width of 40MHz is specified. This is not channel bonding, but a single channel withdouble the older 20 MHz channel width, thus using two adjacent 20 MHzbands. This allows direct doubling of the PHY data rate from a single 20MHz channel, but the MAC and user level throughput also depends on otherfactors so may not double. The 5 GHz band, which is adjacent to the 5.9GHz band, allows for many channels, but no high velocity operation.

It is noted that the Third Generation Partnership Project (3GPP) LongTerm Evolution (LTE) standard is designed for use with vehicularenvironments. However, the LTE specification was designed with referenceto a static macrocell providing service to a mobile user equipment (UE).When a moving UE is accessing a high-powered macrocell at a distance,the effective angular velocity of the UE at the macrocell is reducedowing to the distance the macrocell has from the UE, allowing themacrocell to maintain coverage of the UE. However, a moving small cellsuffers from not only comparatively less power, but also increasedangular velocity relative to UEs that enter its coverage zone. As well,as the UEs themselves may be in motion, the likelihood that a movingsmall cell can maintain coverage of UEs that transit through itscoverage zone is further reduced. LTE is not designed forinter-vehicular communication.

In embodiments directed toward the access side of a network, aprocessing module, which may be a self-organizing network (SON) module,is designed to receive location data, such as global positioning system(GPS) data, of a vehicle and to process that data to determine aninstantaneous or average velocity, a change in velocity as a function oftime (i.e., acceleration), or both. If the SON module detects anincrease in velocity, it can transmit a decrease power command to aradio base station or radio node in the moving vehicle. The decreasepower command could include for example an amount by which to decreasepower. The decrease power command could also be based on a desiredcoverage area. The decrease power command could also include a commandto decrease power at certain intervals. The decrease in power could alsobe preconfigured. Decreasing power as velocity is increased serves threepurposes: (1) the interference from the cell within which the node ofinterest is operating will be reduced from the perspective of the macroor other neighboring cells; (2) the number of unwanted handovers isreduced, thereby increasing the quality of service from a UEperspective; and (3) an unwanted/interfering cell is not introduced intoan area, which may be useful in the case of a self-organizing networkthat adjusts coverage based on cells in the area, among other purposes.

In some embodiments, the decreased power level may be configured suchthat the base station may provide high-speed coverage and access tomobile devices in a moving vehicle which also houses the base station.For example, a mobile base station may be placed inside a vehicle, suchas a car, a bus, a plane, or a train. Coverage in the case that thevehicle exceeds 60 miles per hour should be provided to, but limited to,to mobile devices within the vehicle.

In some embodiments, the SON module could determine that velocity isdecreasing, in which case it could send a command to the radio node toincrease its transmit power. By increasing transmit power, the radionode may: (1) fill coverage voids; (2) provide service to neighboringUEs; and (3) aid in decongesting the network, among other beneficialeffects.

In embodiments directed toward the backhaul side of a network, a SONmodule could be configured to determine if velocity has increased abovea certain threshold, such as 60 miles per hour. If the velocity doesexceed this threshold, the SON module could send a command to the radionode to switch the wireless local area network (WLAN) radio operationinto a different mode for 802.11-based backhaul to 5.9 GHz band WLANradio operation. Some advantages of making this switch are: (1) thecorresponding access cell is also reduced to serve fewer UEs, as perabove; (2) by reducing the channel width, the service being provided toUEs should remain constant, as opposed to being degraded; and (3)seamless operation can continue at higher velocities.

In an alternate embodiment also directed toward the backhaul side of anetwork, a SON module could detect a decrease in velocity below acertain threshold, such as 60 miles per hour. If the velocity fallsbelow the threshold, the SON module could issue a command to a radionode to switch from the 5.9 GHz to the standard 5 GHz Wi-Fi band. Somebenefits of performing this switch could be (1) serving more UEs; and(2) using channel bonding to provide a better user experience.

In some embodiments, the mobility data may include GPS or otherposition, velocity, acceleration, relative position, changes in RSSI orother radio power strength from a known radio transmitter, or othermobility data. Although a threshold of 60 miles per hour is describedabove, an equivalent threshold for each of the other mobility dataparameters could be used in some embodiments.

FIG. 1 is a schematic drawing of a mobile base station deploymentscenario, in accordance with some embodiments. Vehicle 101 with mobilebase station 102 is shown. Vehicle 101 is connected to macrocell 103 viaa wireless backhaul connection 104. Small cells 106 and 109 areconnected to macrocell 103 via wireless backhaul connections 107 and110, respectively. Small cell 106 has coverage area 108. Small cell 109has coverage area 111. Macrocell 103 has coverage area 112. Vehicle 101is on its way to disaster site 113, in order to provide radio access toa first responder 114.

Mobile base station 102 has a maximum coverage area 105. However, whilethe vehicle is in motion, Mobile base station 102 reduces its coveragearea to the area shown as 115, by reducing the transmit power of themobile base station. By reducing the coverage area, mobile base station102 does not interfere with small cells 106 and 109, or with theirwireless backhaul connections 107 and 110, and also does not cause otheruser devices to connect and then lose connectivity when vehicle 101exits the proximity of the other user devices. However, the reducedcoverage area 115 still permits devices within the vehicle to utilizethe wireless backhaul connection 104 to macrocell 103. The wirelessbackhaul connections may be LTE connections, or they may be 802.11 Wi-Ficonnections, or they may be mesh connections, or some combinationthereof.

Alternatively, mobile base station 102, which may be using an LTE bandor a 5 GHz radio frequency band, may switch modes to another radiofrequency band, such as the 5.9 GHz frequency band. The IEEE 802.11pamendment, which uses the 5.9 GHz frequency band, is designed to be usedin an inter-vehicular networking environment, and at vehicular speeds.Use of a 5.9 GHz radio access network will therefore not disruptcommunications on other frequency bands, such as the LTE or 5 GHz bands,while still permitting communications inside of and between vehicles.Use of the 5.9 GHz band will also not interfere with the use of LTEwireless backhaul connection 104.

FIG. 2 is a flowchart depicting a method for changing access networkpower, in accordance with some embodiments. At step 201, a radio accessnetwork (RAN) is in an active state and is transmitting an access signalfor mobile devices to attach. For example, a mobile eNodeB may broadcastits availability for UEs to attach. At step 202, the position and/orspeed of the mobile base station is monitored. The position may bemonitored using a GPS receiver in the mobile base station itself, insome embodiments. Alternatively, the position and/or speed may bemonitored by a GPS receiver in the vehicle in which the base station islocated, or in a remote control center performing management of thevehicle, or at a server in the cloud monitoring the position of thevehicle, or at another location which may not necessarily be at thevehicle itself.

At step 203, the position and/or speed of the mobile base station isused to determine whether the mobile base station is traveling atgreater than a speed threshold, which as shown is 60 miles per hour. Anyspeed threshold could be used. In some embodiments, the speed thresholdis based on the performance specification of the particular accessnetwork being provided by the mobile base station. For example, if LTEis the access medium, step 203 could use a threshold approximately equalto the speed of a moving car or train, i.e., between 50 and 150 milesper hour. Alternate access media such as Wi-Fi could use differentthresholds.

If, at step 203, the mobile base station is determined to be movingfaster than the threshold, execution continues at step 204. At step 204,the transmit power of the access RAN is reduced. Execution continues atstep 205, where that position and/or speed of the mobile base station ismonitored to determine when the vehicle reaches a slower speed.Monitoring continues until a new determination is performed at step 203.

Alternatively, if, at step 203, the mobile base station is determined tobe moving slower than the threshold, execution continues at step 207,and the transmit power of the access RAN is increased, maintained, orrestored as appropriate. In some embodiments, execution returns to step201.

In some embodiments, the mobile base station may be in communicationwith a cloud coordination server, which may be in communication withother base stations. The cloud coordination server may use measurementsfrom UEs, or from other base stations that it manages, to determine theposition or speed of the mobile base station at step 202.

In some embodiments, the steps shown in FIG. 2 may be performed atintervals, such as once per minute or several times per minute. In someembodiments, the steps shown in FIG. 2 may be performed upon a signalreceived from a vehicle computer, such as an onboard navigation systemor a vehicle microprocessor via a vehicular controller area network(CAN) bus. For example, the CAN bus can notify a microcontroller whenthe engine has been started, causing the steps of FIG. 2 to beperformed. Monitoring may also stop when the engine has been stopped, insome embodiments.

In some embodiments, the designated operating band of a suitable radiomay be altered, instead of reducing transmit power. For example, adifferent, private operating band, operated at low power, may be usedinstead of a common 5 GHz band or LTE band.

The algorithms of the present invention are suited for operation onmulti-RAT heterogeneous nodes having self-healing, self-optimization(“SON”) software as part of their operating systems. These multi-RATnodes can be operated in a mesh network and can be stationary or mobile.Details of the multi-RAT nodes and the SON modules are provided in U.S.patent application Ser. Nos. 13/889,631, 14/024,717, and 14/146,857, thecontents of which are hereby incorporated by reference in theirentirety.

FIG. 3 is a schematic diagram of an enhanced base station, in accordancewith some embodiments. Enhanced base station 300 may be an eNodeB foruse with LTE, and may include processor 302, processor memory 304 incommunication with the processor, baseband processor 306, and basebandprocessor memory 308 in communication with the baseband processor.Enhanced eNodeB 300 may also include first radio transceiver 310 andsecond radio transceiver 312, internal universal serial bus (USB) port316, and subscriber information module card (SIM card) 318 coupled toUSB port 314. In some embodiments, the second radio transceiver 312itself may be coupled to USB port 316, and communications from thebaseband processor may be passed through USB port 316.

In some embodiments, processor 302 may be coupled to a globalpositioning system (GPS) module 340. GPS module 340 may provideinformation to the processor regarding the location of the mobile basestation. GPS module 340 may be connected to a GPS antenna 341 locatedoutside the device, preferably on the top or roof of the exterior of avehicle in which the base station is mounted, so that the GPS antennacan receive signals from GPS satellites. In some embodiments, the GPSmodule may provide AGPS functionality, and may cooperate with one ormore other wireless modules, such as a WiFi module, to obtain additionalinformation. In environments where the use of the mobile base station isanticipated on a moving vehicle that is underground or out of sight ofthe sky, another positioning system may be used in conjunction withGPS/AGPS so that the position of the mobile base station may beascertained at times when GPS is not available. For example, a subwaytrain outfitted with a mobile base station may use other means, such asbeacons on the track, to determine position. The position calculated bythe GPS module 340 is processed by the processor 302, in someembodiments, to determine velocity. In some embodiments the GPS modulecan provide the velocity directly.

Processor 302 and baseband processor 306 are in communication with oneanother. Processor 302 may perform routing functions, and may determineif/when a switch in network configuration is needed. Baseband processor306 may generate and receive radio signals for both radio transceivers310 and 312, based on instructions from processor 302. In someembodiments, processors 302 and 306 may be on the same physical logicboard. In other embodiments, they may be on separate logic boards.

The first radio transceiver 310 may be a radio transceiver capable ofproviding LTE eNodeB functionality, and may be capable of higher powerand multi-channel OFDMA. The second radio transceiver 312 may be a radiotransceiver capable of providing LTE UE functionality. Both transceivers310 and 312 are capable of receiving and transmitting on one or more LTEbands. In some embodiments, either or both of transceivers 310 and 312may be capable of providing both LTE eNodeB and LTE UE functionality.Transceiver 310 may be coupled to processor 302 via a PeripheralComponent Interconnect-Express (PCI-E) bus, and/or via a daughtercard.As transceiver 312 is for providing LTE UE functionality, in effectemulating a user equipment, it may be connected via the same ordifferent PCI-E bus, or by a USB bus, and may also be coupled to SIMcard 318.

SIM card 318 may provide information required for authenticating thesimulated UE to the evolved packet core (EPC). When no access to anoperator EPC is available, local EPC 320 may be used, or another localEPC on the network may be used. This information may be stored withinthe SIM card, and may include one or more of an international mobileequipment identity (IMEI), international mobile subscriber identity(IMSI), or other parameter needed to identify a UE. Special parametersmay also be stored in the SIM card or provided by the processor duringprocessing to identify to a target eNodeB that device 300 is not anordinary UE but instead is a special UE for providing backhaul to device300.

Wired backhaul or wireless backhaul may be used. Wired backhaul may bean Ethernet-based backhaul (including Gigabit Ethernet), or afiber-optic backhaul connection, or a cable-based backhaul connection,in some embodiments. Additionally, wireless backhaul may be provided inaddition to wireless transceivers 310 and 312, which may be Wi-Fi302.11a/b/g/n/ac/ad/ah, Bluetooth, ZigBee, microwave (includingline-of-sight microwave), or another wireless backhaul connection. Anyof the wired and wireless connections may be used for either access orbackhaul, according to identified network conditions and needs, and maybe under the control of processor 302 for reconfiguration.

Other elements and/or modules may also be included, such as a homeeNodeB, a local gateway (LGW), a self-organizing network (SON) module,or another module. Additional radio amplifiers, radio transceiversand/or wired network connections may also be included. The SON modulemay be configured to provide transmit power increase/decreasefunctionality, radio band switching functionality, or communicationswith another remote SON module providing, for example, these types offunctionality, in some embodiments. The SON module may be used toperform the steps of FIG. 2 and may execute on the general purposeprocessor 302.

Processor 302 may identify the appropriate network configuration, andmay perform routing of packets from one network interface to anotheraccordingly. Processor 302 may use memory 304, in particular to store arouting table to be used for routing packets. Baseband processor 306 mayperform operations to generate the radio frequency signals fortransmission or retransmission by both transceivers 310 and 312.Baseband processor 306 may also perform operations to decode signalsreceived by transceivers 310 and 312. Baseband processor 306 may usememory 308 to perform these tasks.

In some embodiments, the radio transceivers described herein may be basestations compatible with a Long Term Evolution (LTE) radio transmissionprotocol or air interface. The LTE-compatible base stations may beeNodeBs. In addition to supporting the LTE protocol, the base stationsmay also support other air interfaces, such as UMTS/HSPA, CDMA/CDMA2000,GSM/EDGE, GPRS, EVDO, other 3G/2G, legacy TDD, or other air interfacesused for mobile telephony. In some embodiments, the base stationsdescribed herein may support Wi-Fi air interfaces, which may include oneor more of IEEE 802.11a/b/g/n/ac/af/p/h. In some embodiments, the basestations described herein may support IEEE 802.16 (WiMAX), to LTEtransmissions in unlicensed frequency bands (e.g., LTE-U, LicensedAccess or LA-LTE), to LTE transmissions using dynamic spectrum access(DSA), to radio transceivers for ZigBee, Bluetooth, or other radiofrequency protocols, or other air interfaces. In some embodiments, thebase stations described herein may use programmable frequency filters.In some embodiments, the base stations described herein may provideaccess to land mobile radio (LMR)-associated radio frequency bands. Insome embodiments, the base stations described herein may also supportmore than one of the above radio frequency protocols, and may alsosupport transmit power adjustments for some or all of the radiofrequency protocols supported. The embodiments disclosed herein can beused with a variety of protocols so long as there are contiguousfrequency bands/channels. Although the method described assumes asingle-in, single-output (SISO) system, the techniques described canalso be extended to multiple-in, multiple-out (MIMO) systems.

The foregoing discussion discloses and describes merely exemplaryembodiments of the present invention. In some embodiments, softwarethat, when executed, causes a device to perform the methods describedherein may be stored on a computer-readable medium such as a computermemory storage device, a hard disk, a flash drive, an optical disc, orthe like. As will be understood by those skilled in the art, the presentinvention may be embodied in other specific forms without departing fromthe spirit or essential characteristics thereof. For example, wirelessnetwork topology can also apply to wired networks, optical networks, andthe like. The methods may apply to LTE-compatible networks, toUMTS-compatible networks, to Wi-Fi networks, or to networks foradditional protocols that utilize radio frequency data transmission.Various components in the devices described herein may be added,removed, or substituted with those having the same or similarfunctionality. Various steps as described in the figures andspecification may be added or removed from the processes describedherein, and the steps described may be performed in an alternativeorder, consistent with the spirit of the invention. Features of oneembodiment may be used in another embodiment. Accordingly, thedisclosure of the present invention is intended to be illustrative of,but not limiting of, the scope of the invention, which is specified inthe following claims.

1. A mobile base station, comprising: a global positioning system (GPS)module for determining a current location of the mobile base station; avelocity module coupled to the output of the GPS module for determininga current velocity of the mobile base station; and a controller, thecontroller configured to perform steps comprising: determining thecurrent velocity of the mobile base station using the velocity module;comparing the current velocity to a threshold; and switching, based onthe comparison, from a first radio band to a second radio band.
 2. Amethod for providing access to mobile devices at a base station,comprising: determining a current location of the base station;determining, based on the current location, a current velocity of thebase station; comparing the current velocity to a threshold; andswitching, based on the comparison, from a first radio band to a secondradio band.
 3. A method for providing access to mobile devices at a basestation, comprising: determining a current location of the base station;determining, based on the current location, a current velocity of thebase station; comparing the current velocity to a threshold; andreducing transmit power at the base station if the current velocityexceeds the threshold.